Electrical stop mechanism for circular looms



Sept. 13, 1938. F. c. HALE ET AL ELECTRICAL STOP MECHANISM FOR CIRCULAR LOOMS Filed Aug. 28, 1936 ES 9 EWM M M H fln W S E M AA WT War/W ATTORNEYS Patented Sept. 13, 1938 UNITED STATES PATENT oFFicE ELECTRICAL STOP MECHANISM FOR CIR- CULAR LOOMS tion of Delaware Application August 28, 1936, Serial No. 98,274 In Great Britain September 30, 1935 4 Claims.

This invention relates to electrical stopmechanism for circular looms.

U. S. Patent No, 2,027,459 describes electrical stop mechanism adapted to be actuated by a switch in association with each shuttle of a circular loom, the making or breaking of an electrical circuit by means of the switch bringing about the operation of suitable mechanism to cause relative motion between shuttles and warps to cease. As described in the specification, each switch comprises a member disposed near the rear of a shuttle close to one sheet of the warp shed in which the shuttle lies. The shuttle itself carries a rod slidable towards the member when influenced by the breaking or jamming of the warp threads. As the sliding rod passes through the warp sheet into contact with the switch member, the contact points of the switch are opened or closed as the case may be to bring weaving rapidly to an end. In order to facilitate the location of the defect, the switches are preferably arranged to remain in the new position to which the operating rod has brought them, it then being necessary to re-set the switch after correction of the defect in order to enable the loom to be re-started.

The present invention has particular reference to switches of the type just mentioned.

According to the invention, the switch comprises a member (conveniently a pivoted member) urged by a toggle spring into one of two positions, one in which the member maintains a pair of contacts closed and another in which the member remains in indicating position. Because 01' the toggle mechanism, the member remains in indicating position when acted upon by the faultdetecting means in association with the shuttle, and yet at the same time is readily re-set by an 40 operation calling for the use of one hand only.

A further feature of the invention is that the contact points operate without sliding action, the first movement of the member controlled by the detecting means being to move one contact directly away from the other with the minimum of danger of any sparking occurring as might unduly shorten "the life of the contacts.

A particular form of toggle operating switch mechanism suitable for looms operating with a closed electric stop circuit will now be described with reference to the accompanying drawing in which Fig. 1 is a diagrammatic vertical section of part of a circular loom;

Fig. 2 is a diagrammatic plan view, on a larger scale showing a shuttle and its associated switch; and

Fig. 3 is a diagrammatic plan view showing the mechanism for starting and stopping the loom, together with the electrical connections.

Referring to Fig. 1, a shuttle l is disposed between warp sheets 2, 3 by means of a rotatable vane wheel i passing through the outer warp sheet 3 into engagement with rollers 5 in the shuttle body. A roller 6 mounted on a substantially vertical axis in the shuttle body engages a race I disposed inside the inner sheet 2.

The shaft 8 of the vane wheel 4 is carried by a column 9, mounted on a rotatable ring l0 driven through teeth H by means not shown, round the loom periphery. By reason of the engagement of the vane wheel 4 with the shuttle l, the shuttle is carried round the loom at the same speed as the ring l0. As shown in Fig. 2 a rod 12 is slidably mounted in the shuttle I and carries at its front end a feeler l3 intended to engage incorrectly shedded warp threads as are occasioned by, for example, breakage of a warp thread. Such jamming propels the rod l2 rearwardly of the shuttle, so that its rear end M, which normally lies at the rear of the outer warp sheet 3 as shown in Fig. 1 in full lines, is caused to pass through the sheet 3 as shown in dotted lines.

Disposed opposite the rear end of the rod l2 and carried in any convenient way by the rotatable ring in is a switch I5 comprising two pivot points [6, I! for two members l8, [9 of insulating material which carry respectively contact blades 20, 21. The blade 20 extends towards the shuttle so that its end lies opposite the end M of the rod l2, but outside the sheet 3. The other end of the blade is intended to make contact with the blade 2| at a point remote from the shuttle, and, therefore, away from the warps. A pin 22 on the member 19 engages a slot 23 and member l8 and also a spring 24 enclosed in the member [8. As is clear from Fig. 2 the members l8, l9 constitute a toggle serving to hold the blades 20, 2! in the separated position shown in dotted lines. Leads 25, 26 connect the switches l5 of the several shuttles incorporated in the loom in series as shown in Fig. 3, the leads being connected to slip rings 21 to make electrical connection with a circuit including electro-magnets 28, 29, the first of which, when energized, serves to hold a brake band 30 from the periphery of the shuttle-supporting ring 10, and the second, when energized, to provide an electric link between a starting handle 3| and the clutch 32 through which the loom is driven. Details of the brake and clutch mechanism, together with the controlling electro-magnets are to be found in United States Patent No. 2,091,333.

When the feeler I3 detects a warp jam, the blade 20 of the switch I5 is rotated clockwise, and separated from the blade 2| to open the electromagnet circuits, so that the brake 30 is applied, and simultaneously the clutch 32 is disengaged to bring weaving rapidly to an end. Because of the toggle construction of the switch IS, the blade 20 remains in the position shown in dotted lines, and serves as a clear indication of the shuttle adjacent to which the fault arose. Upon correction of the fault the blade 20 is restored by the operative to the position shown in full lines, and re-engages the blade 2|, the toggle mechanism holding the blades in this position. The toggle mechanism enables this resetting to be effected very easily by the operative using one hand only.

By reason of their pivotal mounting, the blades 20, 2| move away from each other without sliding action.

Having described our invention, what We desire to secure by Letters Patent is:-

1. In a circular loom having shuttles provided with means to detect yarn breakage or other yarn failures and an electrically-operated stop mechanism, a switch comprising a member adapted to be engaged by the detecting means, a pair of pivoted members each including a contact point connected in the stop mechanism circuit, one member having an extension adapted to be engaged by the detecting means, and toggle means connecting the members and adapted to hold the points either open or closed.

2. In a circular loom having shuttles provided with means to detect yarn breakage or other yarn failures and an electrically-operated stop mechanism, a switch comprising a member adapted to be engaged by the detecting means, a contact point carried by said member, a second member, a second contact point carried by said second member, both points being connected in the stop mechanism circuit, and toggle means connecting the members and adapted to hold the points either open or closed.

3. In a circular loom having shuttles provided with means to detect yarn breakage or other yarn failures and an electrically-operated stop mechanism, a switch comprising a member adapted to be engaged by the detecting means, a contact point controlled by said member, a second member, a second contact point carried by said second member, both points being connected in the stop mechanism circuit, and toggle means adapted, upon engagement of the said member by the detecting means, to open or close the points and hold them in the open or closed position.

4. In a circular loom having shuttles provided with means to detect yarn breakage or other yarn failures and an electrically-operated stop mechanism, a switch comprising a member adapted to be engaged by the detecting means, a contact point carried by said member, a second member disposed substantially at right angles to said member, a second contact point carried by said second member, both points being connected in the stop mechanism circuit, and toggle means connecting the members and adapted to hold the points either open or closed, the relative disposition of the members ensuring that the contact points, at the moment of breaking, move directly away from each other, thereby avoiding sliding contact.

FRANK CORBYN HALE. JAMES RUSSELL YORKE. 

